1. Field of the Invention
The present invention relates to an optical disk and an optical disk apparatus in which information is optically recorded and reproduced on a predetermined recording layer on the disk.
2. Background of the Invention
Recently, optical disks have been developed and many of them have been commercialized. The optical disks use metal, coloring matter, and the like, in information recording layers and are capable of being reproduced after recording has been made. However, the information which has been once recorded cannot be re-recorded or written over. In spite of such an inconvenience, attention is particularly paid to the optical disks because the optical disks have a capacity relatively larger than other recording media.
In a conventional optical disk apparatus, on the other hand, a pickup (that is, an information detecting point) is caused to repeatedly trace the last track (a pause track) on which the recording/reproducing operation was ended at the last time. As shown in FIG. 5, the pickup repeatedly traces a spiral track with repeated track jumps in a so-called pause mode in which the information recording/reproducing operation is temporarily interrupted (or in a wait state). If one and the same pause track is thus repeatedly traced for a long time, however, there has been a risk of damage of recorded information on the pause track depending on the material of a recording layer even if the intensity of light is adjusted in advance to be small enough not to cause any substantial change in the recorded information in a normal reproducing operation.